In <em>The Grapes of Wrath</em>, Mae and Al run a diner on the way to California. On this particular day, a poor family came in and wanted to buy a loaf of bread for a dime. Mae replied that they do not sell bread as it was a diner not a grocery store and that the man should buy a sandwich instead which he could not afford.
In the end, after some prompting from her husband Al, she sells the loaf of bread to the man and shows an extra kindness to his children by underselling some candy to them.
A flashback tells something from the past so the answer would have to be (A) this is because of the use of the word recall. In every other option the verb is present or future tense instead of past tense.